Question

The given diagram depicts the phase change of ice on heating. In the graph temperature has been plotted against time elapsed.

Which of the following statements is correct?

• A. A B represents ice and water are not in the thermal equilibrium
• B. At B water starts boiling
• C. At C all the water gets converted into steam
• D. CD represents water and steam in equilibrium at boiling point

Answer 1

Answer: (D)

In the given graph, AB represents no change in temperature with time. It means ice and water are in thermal
equilibrium. BC shows the change in temperature with time. CD represents a constant temperature $\left(\right.100℃\left.\right)$ with time.
It means, water and steam are in thermal equilibrium at boiling point.